I get asked certain fishing questions over and over again, and one of the most popular is: what's the best trolling speed? Naturally, this depends on what species you're trolling for, and what types of lures and/or baits you're trolling with. What people often fail to realize, however, is that even for a given species, specific lures, and well-defined conditions, the "best" trolling speed changes. Often.
The bottom line: which speed is best can vary depending on factors ranging from the shape of your boat's hull to the fish's mood. And even worse, it can change from hour to hour, much less day to day. This, however, doesn't mean there aren't a few constants we can work with to get our boats going at just the right speed as we troll. First off, judge speed by looking at your own lures or baits. Once you've picked a speed, hold those lures or baits over the side next to the boat and watch them. If they don't have much action, bump the speed up a bit. If they spin or look just plain wrong, slow it up a click. The biggest mistake most anglers make when searching for the best trolling speed is, bar none, failing to watch their offering for a minute or two before sending it back to the fish.
Okay: now that you know the boat speed your lures look good at, you have a base to work with. The next issue most folks forget about is that as soon as you make a significant change of direction your boat's speed through the water is going to change. Current and wind will conspire to push your boat this way or that, and suddenly, your lures could be moving through the water several knots more, or less, than they were a few seconds ago. You have two ways to react: change your boat speed to make up for the difference, or simply make sure that you're always trolling cross-current (or wind) instead of with or against it. Going across the prevailing force is always my choice of tactics, since it's more or less idiot-proof (a distinct advantage, in my case).
Here's one more uber-important tip to keep in mind when you're searching for the best trolling speed: if what you're doing isn't working, make a change. And I mean soon; don't wait for half the day to go by before you try speeding up or slowing down. If you see fish on the meter and 10 minutes go by without a bite, make a change. If you get a strike, pay attention to what the speed was and continue changing and tweaking it until you get consistent bites. When it comes to fishing patience is not always a virtue - and remember, as soon as you figure out what the best trolling speed is, it will probably change.